Ca2+-cardiolipin interaction in a model system. Selectivity and apparent high affinity.

P M Sokolove; J M Brenza; A E Shamoo

doi:10.1016/0005-2736(83)90184-0

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PubMed · 6191772

Ca2+-cardiolipin interaction in a model system. Selectivity and apparent high affinity.

P M Sokolove·J M Brenza·A E Shamoo

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Abstract

The interaction of cardiolipin with Ca2+ was assessed by measuring the cardiolipin-mediated extraction of 45Ca2+ from an aqueous to an organic (methylene chloride) phase. Cardiolipin binds Ca2+ with high affinity [Kd(apparent) = 0.70 +/- 0.17 microM (S.D.)]. Cation-cardiolipin interactions are selective. Interaction of cardiolipin with Ca2+ is insensitive to Na+, but is inhibited by divalent cations with Mn2+ greater than Zn2+ greater than Mg2+. In addition La3+ and Ruthenium red are particularly potent inhibitors of Ca2+ binding by cardiolipin. Cardiolipin-mediated extraction of Ca2+ into an aqueous phase is also inhibited by phosphatidylcholine. Inhibition of Ca2+-cardiolipin interaction by phosphatidylcholine (a phospholipid known to stabilize the bilayer conformation) may implicate inverted, non-bilayer lipid structures in the binding.

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Calcium Carbon Radioisotopes Cardiolipins Cations, Divalent Kinetics Lanthanum Models, Biological Ruthenium Red Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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P M Sokolove, J M Brenza, A E Shamoo. 1983-07-13. Ca2+-cardiolipin interaction in a model system. Selectivity and apparent high affinity.. https://doi.org/10.1016/0005-2736(83)90184-0

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